Cowboy, a wedge or two and an X-27 will free a lot of stuck saws, and is lighter than a second saw! I'm sometimes surprised how well it works. (but I always have a second saw just in case).
You're right of course, Mike and @benp . I always have wedges and the maul with me, you'll note one in the log in one of yesterday's pics. This particular cut was at a splintered fork and the cut closed up rapidly early in the cut and I wasn't quick enough to get the saw out. Too early to get a wedge in in any case. The other saw was a few metres away while I would have had to walk at least 25 whole metres to get the maul. And back. I've never actually needed to use another saw to cut one out but on this particular occasion it was the nearest to hand. Still, it wasn't the worst example of ****uppery I committed yesterday. I'm so embarrassed I'm not sure I can bring myself to admit it in public.